A novel technique for mapping biopsy of bile duct cancer.

BACKGROUND : Accurate preoperative assessment of the longitudinal extension of perihilar cholangiocarcinoma (PHCC) is essential for treatment planning. Mapping biopsies for PHCC remain challenging owing to technical difficulties and insufficient sample amounts. The aim of this study was to investigate the usefulness of a novel technique for mapping biopsies of PHCC. METHODS : Our novel method focused on a biliary stent delivery system for mapping biopsies. Fifty patients with PHCC undergoing endoscopic transpapillary mapping biopsy using the novel method were reviewed from August 2015 to June 2019. RESULTS : The median number of biopsy samples was six (range 1 - 17), and the rate of adequate sampling was 91.4 % (266 /291). Biopsy from the intrahepatic bile duct was possible in 82.0 % of patients (41 /50), and negative margins were confirmed in the resected specimens from 34 /39 patients who underwent surgery (87.2 %). None of the patients had post-endoscopic retrograde cholangiopancreatography pancreatitis. CONCLUSIONS : With our novel method, accurate assessment of the longitudinal extension of PHCC might be expected with minimal trauma to the duodenal papilla.